Todd Vance: "I think this is the "second" post PC era. The first was after the fad with cheap home computers---the Vic 20, the Apple II, the PCjr, ah the days! They went away "when people got tired of boxes that go 'bing'". "
I have to disagree with this. Yeah, once the novelty wore off, there was a burnout in the early 1980s on the absolute lowest price point computers that didn't really do much (the Timex Sinclair and some of the TRS-80s come to mind, maybe the TI-99), but of the computers you describe above only the VIC-20 might qualify as a computer that just goes 'bing,' and the VIC was still pretty capable for its time. The Apple II was an extremely versatile computer that spawned the first spreadsheet program and some of the first word processors, and with development was a viable competitive product into the 1980s. The PC Jr. had its issues, but the very similar Tandy machines were successful, as obviously was the full-strength IBM PC and the dissimilar but still very capable Commodore 64.
You seem to be implying that PC buying hit a big trough after the early 1980s, until the second PC era began in the early 1990s with the Internet and multimedia, and I just don't think that's true. It's not as if people purchased most early PCs as a fad, and subsequently got rid of computers altogether until the 1990s. Instead, they upgraded. People who bought VIC-20s may have replaced them with a Commodore 64. People who bought IBM machines may have replaced them with 286s, then 386s. People who bought Apple IIs may have subsequently moved on to Macs. Customer adoption of the PC just kept building through the 1980s as technology improved, but that doesn't mean that the early PCs were a fad.
I do agree that the web and multimedia accelerated the process, though. Access to amazing new quality and quantity of content really helped increase adoption.

What was Microsoft's original mission? In 1975, Gates and Allen form a partnership called Microsoft. Like most startups, Microsoft begins small, but has a huge vision – a computer on every desktop and in every home. The existential crisis facing Microsoft is that they achieved their missi...

Wojtek Swiatek: "The graph, although interesting, tries to compare devices which are not comparable."
Agreed, but even more so, I'm really skeptical that you can draw any real conclusions from that graph (let alone the conclusions the author makes) based on the differences in time periods measured.
The Applie ]['s starting point is 1977, and the Mac's starting point is 1984. You can't compare the speed of market penetration for expensive and exotic personal computers in 1977, when nobody really know what a personal computer could do and there was no established software industry, with the potential of selling a much less expensive and well-understood device to a marketplace of highly tech-savvy people.
You may as well put the automobile and television set on that chart too - you'd find that the curves are much less steep than the personal computer, even though those products were absolutely revolutionary and became ubiquitous to our everyday life. America is just a different consumer environment now than it was when the PC was new, or when the TV and automobile were new.
Specifically, America in the last decade is far quicker to learn about and embrace new technology of any kind than it was receptive to computers in 1977-1984. The whole marketplace is way too different to assume that the difference in the curves can be attributed to the factors called out in the article.
Overall I liked and enjoyed the article and the comments, but that really stood out as a poor interpretation of data.

What was Microsoft's original mission? In 1975, Gates and Allen form a partnership called Microsoft. Like most startups, Microsoft begins small, but has a huge vision – a computer on every desktop and in every home. The existential crisis facing Microsoft is that they achieved their missi...